1. Field of the Invention
The present invention is generally related to optical phase detectors, and more particularly to a dynamic optical phase detection instrument that linearly detects the state of optical phase over a set of optical phase states spanning several optical wavelengths.
2. Description of the Prior Art
Present optical phase state detectors are limited in the degree of change in the optical phase state and the upper dynamic response that they can follow. Small fast changes in the optical phase are typically detected using conventional optical interferometry. In such conventional optical interferometry, the light of which the phase state is to be detected is optically interfered with a reference light beam at the same wavelength. The resulting state of interference indicates the relative optical phase state of the light and is detected by measuring the optical intensity of the interference. The resulting interference pattern creates a change in optical intensity that varies sinusoidally as a function of the relative state of phase of the light in the two interfering beams. The magnitude of the varying intensity is correlated to a particular state of optical phase of the light to be detected. However, this conventional approach only allows for the detection of an optical phase change associated with the variation of a single wavelength of the light to be detected. Further optical phase change repeats the described intensity variation and creates ambiguous results.
What is needed, therefore, is an apparatus and a method for dynamically detecting the state of optical phase of an object that spans several wavelengths of light.
In addition, it is desirable to produce an indication that is linearly related to the state of optical phase of the object.